Assemblies for use in determining the relative rate of delivery of a liquid sprayed through spray nozzles along an elongate spray zone at a specific distance from the spray nozzles are known. U.S. Pat. No. 4,539,842 and German Utility Model No. 6804628 provide examples. The assembly described in U.S. Pat. No. 4,539,842 includes a tray-like member having evenly spaced alternating first ridge portions and recessed portions defining along its upper surface a multiplicity of parallel adjacent elongate troughs extending from one edge, and an end ridge portion transverse of the troughs along that first edge that provides and end wall for the troughs. The tray like member is adapted to receive removable collector test tubes longitudinally aligned with ends of the troughs opposite its first end ridge, and is mounted on a height adjustable cart so that troughs can be positioned beneath an elongate spray zone at a specific distance from nozzles producing the spray zone with the troughs extending transverse of the elongate spray zone. After liquid is sprayed through the spray nozzles upon the upper surface, the assembly can be tipped so that the liquid collected in the troughs will run along the troughs into the test tubes and the comparative resultant levels of liquid the test tubes will provide a visual indication of the uniformity of the amount of liquid being delivered by the nozzles along the spray zone at the specific distance. While the assembly described in U.S. Pat. No. 4,539,842 should be effective in providing a visual indication of the uniformity of the amount of liquid being delivered by nozzles along a spray zone at specific distances from the nozzles, it has a large, complex and expensive structure so that some persons that might benefit from using it may not do so because of its expense, and/or because of the inconvenience of transporting and storing it between uses.